The continuing goal of the Flow Cytometry Core is to provide acquisition and analysis of any flow cytometry data needed by program investigators. For evaluation of plasma, serum, and cell culture supernatants, the core provides staining, acquisition, and analysis of expression of as many as 30 cytokines / chemokines / cytotoxic proteins / phospho-proteins per sample using the Cytometric Bead Array (CBA) multiplexing platform. The core has been providing 8-color immunophenotyping and is preparing to extend this to 10-color detection. The core stains, acquires, and analyzes the levels of expression of intracellular proteins (cytokines such as IL-6, IL-10, IL-12) and phospho-proteins (phospho-Stat3). The Aldefluor assay is employed by the core to examine expression of aldehyde dehydrogenase, which is reportedly expressed at increased levels in cancer stem cells. The core has previously demonstrated the ability of its cell sorter to perform high-purity sorting of gene-transduced cells co-expressing green fluorescent protein (GFP).